[quintushoratius]

That's just like how shampoo companies advise you to "lather, rinse, repeat". It's a great way to boost sales, but besides being unnecessary it's terrible for your hair, your water bill, fish living downstream, and your wallet.

[gs17]

Personally, I've had much better results with repeating, but I haven't bothered to experiment enough to see if it's from "rinse, lather, rinse" or the full "lather, rinse, lather, rinse".

[gumby]

> That's just like how shampoo companies advise you to "lather, rinse, repeat". It's a great way to boost sales.

It’s no accident that they code a loop with no termination condition (except the implicit emptying of the bottle). Really boosts sales!

[ars]

I do occasionally repeat and it does make a difference, but you only need 1/10th as much shampoo the second time.

[guidoism]

I’m curious. What does the second iteration accomplish? Is it dirt and grease that is embedded in your skin? What kind of job do you have if you feel comfortable answering?

[ars]

It's not usually needed, but if I'm really sweaty and sticky the first washing removs dirt, and the second washing adds "squeak" is the best way I can put it.

It just feels cleaner. I assume it's because the additives in the shampoo become overloaded on the first use, and are active on the second.

[guidoism]

I like the squeak too. I recently moved to a place with hard water and so everyone has water softeners. With this super soft water I can't get the squeak ever. It just feels slimy to me.